US6125974A - Vibration damper for vehicle brakes - Google Patents

Vibration damper for vehicle brakes Download PDF

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Publication number
US6125974A
US6125974A US09/070,010 US7001098A US6125974A US 6125974 A US6125974 A US 6125974A US 7001098 A US7001098 A US 7001098A US 6125974 A US6125974 A US 6125974A
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United States
Prior art keywords
vibration
high voltage
control circuit
piezoelectric elements
signal
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
US09/070,010
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English (en)
Inventor
Yukio Nishizawa
Shiro Nakajima
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Advics Co Ltd
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Sumitomo Electric Industries Ltd
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Assigned to SUMITOMO ELECTRIC INDUSTRIES, LTD. reassignment SUMITOMO ELECTRIC INDUSTRIES, LTD. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: NAKAJIMA, SHIRO, NISHIZAWA, YUKIO
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Assigned to ADVICS CO., LTD. reassignment ADVICS CO., LTD. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: SUMITOMO ELECTRIC INDUSTRIES, LTD.
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
    • F16D65/00—Parts or details
    • F16D65/0006—Noise or vibration control
    • F16D65/0012—Active vibration dampers
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
    • F16D55/00—Brakes with substantially-radial braking surfaces pressed together in axial direction, e.g. disc brakes
    • F16D55/02—Brakes with substantially-radial braking surfaces pressed together in axial direction, e.g. disc brakes with axially-movable discs or pads pressed against axially-located rotating members
    • F16D55/22—Brakes with substantially-radial braking surfaces pressed together in axial direction, e.g. disc brakes with axially-movable discs or pads pressed against axially-located rotating members by clamping an axially-located rotating disc between movable braking members, e.g. movable brake discs or brake pads
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
    • F16F15/00—Suppression of vibrations in systems; Means or arrangements for avoiding or reducing out-of-balance forces, e.g. due to motion
    • F16F15/005—Suppression of vibrations in systems; Means or arrangements for avoiding or reducing out-of-balance forces, e.g. due to motion using electro- or magnetostrictive actuation means
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
    • F16D2129/00—Type of operation source for auxiliary mechanisms
    • F16D2129/06—Electric or magnetic
    • F16D2129/12—Electrostrictive or magnetostrictive elements, e.g. piezoelectric

Definitions

  • This invention relates to a vibration damper for vehicle brakes which can prevent squeals of a vehicle wheel brake produced during braking.
  • a wheel brake tends to squeal during braking.
  • Various means have been proposed to prevent such brake squeals.
  • brake vibration dampers disclosed in unexamined Japanese patent publications 4-54324 and 4-54325 are known.
  • the former publication discloses a vibration damper having a piezoelectric vibrator for applying inaudible vibration to friction members (pads), and another vibration damper comprising a piezoelectric detector for detecting vibration of the friction members, and a piezoelectric vibrator for applying inaudible vibration to the pads only while the detector is detecting vibration of the pads.
  • a vibration damper including a piezoelectric vibration detector for detecting vibration of the friction members, and a vibrator means for vibrating the friction members to dampen their vibration according to the detected vibration.
  • the vibrator applies vibration 180 ° out of phase from the vibration detected.
  • both the above two piezoelectric elements are used.
  • the vibration damper systems disclosed in the above two publications apply inaudible vibrations through piezoelectric elements, or vibrate friction members through piezoelectric elements according to the vibration detected to dampen vibration. These systems have various problems.
  • Piezoelectric elements are polarized to produce electric characteristics when pressure is applied to a crystal of e.g. piezoelectric element ZnO 2 , and produce piezoelectricity when the above process is reversed. It is preferable to use piezoelectric vibration detector and vibrator having as large a piezoelectric effect (piezoelectric constant) as possible.
  • Curie temperature is a critical temperature at which a piezoelectric element loses its spontaneous polarization properties and thus its piezoelectricity. Once a piezoelectric element loses its piezoelectricity, it cannot restore its original properties simply by cooling down to normal temperatures.
  • the temperature around piezoelectric elements mounted in a brake caliper can rise to 200° C. or higher. If the ambient temperature approaches or exceeds the Curie temperature of the piezoelectric elements, their performance deteriorates quickly. But it is known that piezoelectric elements that have deteriorated in performance and thus have collapsed orientation of polarization can restore polarization orientation by applying a DC high field.
  • An object of this invention is to provide a vibration damper system which can restore the performance of piezoelectric elements that have deteriorated in performance due to temperature buildup resulting from repeated braking actions.
  • a vibration damper system for a vehicle brake including a vibration detector means comprising piezoelectric elements for detecting vibration produced when a rotary member of the wheel brake is braked by a friction member, a control circuit and a vibrator means comprising piezoelectric element, the vibration detector means transmitting a vibration damping signal to the vibrator means through the control circuit to suppress vibration, the vibration damper system further comprising a high source and changeover means provided along a signal line connecting each of the piezoelectric elements of the vibration detector means and the vibrator means to the control circuit, the control circuit transmitting a changeover signal to one or some of the changeover means in response to a timing signal inputted into the control circuit to apply high voltage to one or some of the piezoelectric elements from the high voltage source.
  • the vibration damper system applies vibration corresponding to the vibration detected by the vibration detector through the vibrator to cancel and suppress vibration. But if the piezoelectric elements are subjected to high temperature due to repeated braking, they will lose their piezoelectric properties.
  • the vibration damper system according to this invention is provided with a changeover means in signal lines connecting each piezoelectric element to the control circuit.
  • a changeover means in signal lines connecting each piezoelectric element to the control circuit.
  • FIG. 1 is a partial sectional view of the disk brake provided with a vibration damper system embodying the invention
  • FIG. 2 is a block diagram of the entire damper system of FIG. 1;
  • FIG. 3 is a graph showing voltage-dependent performance restoration properties.
  • FIG. 1 is a partial section of a disk brake having a vibration damper embodying the invention.
  • the disk brake shown has an opposed type caliper 1.
  • brake pistons 2 are mounted in the caliper 1.
  • a fixing piston 5 is received in each brake piston 2.
  • Vibration detectors 7 and vibrators 8 are bonded or otherwise fixed to the fixing pistons 5 and adapted to be pressed against pads 3 by the respective pistons 5.
  • the pads 3 are brought into frictional contact with a disk rotor 4.
  • Each fixing piston 5 is inserted in the respective brake piston 2 so as to be slidable in the axial direction of the disk with its outer periphery sealed by a piston seal.
  • Brake fluid pressure in a fluid chamber of the caliper 1 is applied to the rear end faces of the brake pistons 2 and the pistons 5 to advance the pistons 5, thus pressing the vibration detectors 7 and the vibrators 8 against the pads 3.
  • machining accuracy of brake parts has no influence on the pressures at which the detectors 7 and vibrators 8 are pressed on the pads. For example, even if the thicknesses of the detectors 7 and vibrators 8 are not so precise, accurate detection and application of vibration are possible.
  • FIG. 2 is a block diagram of the entire vibration damper system for the disk brake shown in FIG. 1.
  • the vibration damper shown has a control circuit 10 which, based on vibrations detected by the vibration detectors 7, transmits a signal to the vibrators 8 to damp vibrations and suppress brake squeals.
  • the control circuit 10 also has the function of restoring the piezoelectricity of one or some of the vibration detectors 7 and vibrators 8 by applying a high DC field to their piezoelectric elements if the circuit 10 receives a timing signal which is produced in a piezoelectricity restoring phase.
  • the vibration damper of this invention has a high voltage source 11 for generating a high voltage using the car battery for actuating the control circuit 10.
  • switches 12a, 12b are connected to detection signal lines A+, A- of each vibration detector 7 so as to be changed over in response to signals through signal lines a1, a2 from the control circuit 10 so that high voltage can be applied through lines B+, B- from the high voltage source 11.
  • the high voltage source 11 shown is a DC--DC converter which steps up 12 V produced by the battery to 60 V.
  • the control circuit 10 activates the piezoelectricity restoration operation while the vehicle brakes are being applied with the vehicle either in motion or at a stop. The fact that the brakes are being applied is detected by a brake actuation detector 13 for detecting the pressure in the master brake cylinder MC.
  • the control circuit 10 receives the signal from the detector and activates the piezoelectricity restoring phase at one of the following five timings:
  • a signal is transmitted to the circuit 10 from the ignition (IGN) switch 14, a travel distance counter 15 or a counter 16 for counting the number of times the brakes are applied.
  • a piezoelectricity restoration function trigger signal (5 V signal) is applied for a predetermined time period to the switches 12a, 12b from a one-shot multivibrator provided in the control circuit 10.
  • a trigger signal is produced based on the signal of the brake pressure detector 13 to apply high voltage to the piezoelectric elements from the one-shot multivibrator for a predetermined time.
  • a trigger signal is produced by e.g. a comparator to apply high voltage to the piezoelectric element from the one-shot multivibrator for a predetermined time period.
  • a trigger signal is produced by e.g. a comparator to apply high voltage to the piezoelectric element from the one-shot multivibrator for a predetermined time period.
  • the piezoelectric elements as the vibration detectors 7 detect vibration of the disk rotor 4 through one of the pads (e.g. inner pad). Based on the signal from the vibration detectors, the control circuit 10 adjusts the phase and amplitude of vibration and applies vibration that is opposite in phase to the vibration of the disk rotor 4 to the other pad (e.g. outer pad) and thus to the disk rotor 4 through the piezoelectric vibrators 8 to suppress vibrations of the disk rotor and thus brake squeals.
  • the temperature in the caliper 1 tends to rise due to friction heat. This deteriorates the piezoelectric characteristics of the piezoelectric elements.
  • the piezoelectricity restoration command signal applied to the switches 12a, 12b is normally 0 volt (low level), thus connecting + and - terminals of the piezoelectric elements to the control circuit 10 through the switches 12a, 12b.
  • control circuit 10 may be provided with a program for measuring the capacitance of each piezoelectric element, comparing it with a reference capacitance and specifying any deteriorated one.
  • the piezoelectricity restoration phase starts at a timing when one of the above-listed five conditions is met.
  • FIG. 3 shows how a piezoelectric element that had deteriorated in piezoelectricity due to the temperature rise at the pad linings to 250° C. restored piezoelectricity by applying a high DC field.
  • 60 V was applied for about one second to the piezoelectric vibration detector or vibrator.
  • the vertical axis indicates the degree of performance deterioration compared with the initial squeal-suppressing performance. From this graph, it is apparent that the performance of the sample dropped by more than 25% from the initial performance and then restored almost completely. It is possible to restore performance by applying voltage only for a short time. Thus, the energy needed for performance restoration is small.
  • the piezoelectric element used in this measurement could withstand a voltage of 150 V.
  • the vertical axis indicates the degree of performance deterioration in terms of capacitance compared with the initial value. From the graph, it is apparent that the application of a voltage of 60 V or more is enough to restore the performance.
  • the degree of performance deterioration was measured in terms of the disk rotor vibration damping rate as follows:
  • the vibration damping rate changed from the initial damping rate of 0.31 times to 0.62 times when deteriorated. It returned to 0.32 times after the performance restoration treatment. Thus, the deterioration effect was about 100%.
  • the piezoelectric elements can restore piezoelectric properties by applying high DC voltage.
  • the reliability and durability of the piezoelectric elements can be improved.

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Aviation & Aerospace Engineering (AREA)
  • Braking Arrangements (AREA)
  • Vibration Prevention Devices (AREA)
US09/070,010 1997-05-12 1998-04-30 Vibration damper for vehicle brakes Expired - Fee Related US6125974A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP9120995A JPH10311354A (ja) 1997-05-12 1997-05-12 車両ブレーキ用制振装置
JP9-120995 1997-05-12

Publications (1)

Publication Number Publication Date
US6125974A true US6125974A (en) 2000-10-03

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Country Status (4)

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US (1) US6125974A (ja)
EP (1) EP0878634A1 (ja)
JP (1) JPH10311354A (ja)
KR (1) KR19980086867A (ja)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6302244B1 (en) * 2000-04-07 2001-10-16 The Boeing Company Brake squeal attenuator apparatus and method
US6412880B1 (en) * 2000-03-29 2002-07-02 Honeywell Commercial Vehicle Systems Co. Combined power supply and electronic control circuit for ABS
US6742632B2 (en) * 1998-12-01 2004-06-01 Lucas Industries Plc Apparatus with vibration-damped component, especially a brake
US20040174067A1 (en) * 2003-03-07 2004-09-09 Advics Co., Ltd. Vehicle brake squeal control device
US20040178675A1 (en) * 2003-03-13 2004-09-16 Advics Co., Ltd. Vehicle brake squeal control device
US20040206589A1 (en) * 2003-04-15 2004-10-21 Masahiko Kamiya Vehicle brake system for preventing brake noise
US20050039990A1 (en) * 2003-07-25 2005-02-24 Messier-Bugatti Actuator for an electromechanical brake, a brake including such an actuator, a vehicle including at least one such brake, and a method of implementing said actuator
US20050242664A1 (en) * 2004-04-29 2005-11-03 Thrush Christopher M Brake force sensor
US20060108861A1 (en) * 2004-11-23 2006-05-25 Mando Corporation Electronic control brake system with piezoelectric actuator

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19931081A1 (de) * 1999-07-06 2001-01-11 Bosch Gmbh Robert Verfahren zur Variation der Bremskraft einer Fahrzeugbremse und Fahrzeugbremse
KR100897111B1 (ko) * 2002-11-25 2009-05-14 현대자동차주식회사 차량의 진동소음 저감구조
DE10313990B4 (de) * 2003-03-27 2005-10-13 Daimlerchrysler Ag Verfahren sowie Vorrichtung zur Reduktion von Bremsgeräuschen
RU2555082C1 (ru) * 2014-05-19 2015-07-10 Федеральное государственное бюджетное образовательное учреждение высшего профессионального образования "Волгоградский государственный технический университет" (ВолгГТУ) Дисковый тормоз с функцией динамического гасителя колебаний
CN106641027B (zh) * 2016-12-01 2018-11-06 陕西法士特齿轮有限责任公司 一种制动器

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0454324A (ja) * 1990-06-22 1992-02-21 Aisin Seiki Co Ltd 車両用制動装置
JPH0454325A (ja) * 1990-06-22 1992-02-21 Aisin Seiki Co Ltd 車両用制動装置
US5175687A (en) * 1989-09-11 1992-12-29 Toyota Jidosha Kaisha Suspension control system
JPH06245552A (ja) * 1993-02-12 1994-09-02 Sumitomo Metal Ind Ltd 圧電アクチュエータの特性回復方法
JPH07111788A (ja) * 1993-10-12 1995-04-25 Olympus Optical Co Ltd 超音波振動子の駆動装置
EP0748947A1 (en) * 1995-06-13 1996-12-18 Sumitomo Electric Industries, Inc. Vibration damper for use in a disk brake

Family Cites Families (2)

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JPS6198165A (ja) * 1984-10-17 1986-05-16 Nippon Soken Inc 圧電アクチユエ−タ制御装置
JPH0832038A (ja) * 1994-07-15 1996-02-02 Komatsu Electron Metals Co Ltd 貼り合わせｓｏｉ基板の製造方法および貼り合わせｓｏｉ基板

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5175687A (en) * 1989-09-11 1992-12-29 Toyota Jidosha Kaisha Suspension control system
JPH0454324A (ja) * 1990-06-22 1992-02-21 Aisin Seiki Co Ltd 車両用制動装置
JPH0454325A (ja) * 1990-06-22 1992-02-21 Aisin Seiki Co Ltd 車両用制動装置
JPH06245552A (ja) * 1993-02-12 1994-09-02 Sumitomo Metal Ind Ltd 圧電アクチュエータの特性回復方法
JPH07111788A (ja) * 1993-10-12 1995-04-25 Olympus Optical Co Ltd 超音波振動子の駆動装置
EP0748947A1 (en) * 1995-06-13 1996-12-18 Sumitomo Electric Industries, Inc. Vibration damper for use in a disk brake

Non-Patent Citations (4)

* Cited by examiner, † Cited by third party
Title
Patent Abstracts of Japan, vol. 018, No. 641. *
Patent Abstracts of Japan, vol. 095, No. 007. *
Yukio Nishizawa et al., "Electronic Control Canceling System for a Disc Brake Noise", Proceedings of the 1997 International Congress and Exposition; Detroit, MI., Feb. 27, 1997, vol. 1229, Feb., 1997, pp. 83-88, XP002075840.
Yukio Nishizawa et al., Electronic Control Canceling System for a Disc Brake Noise , Proceedings of the 1997 International Congress and Exposition; Detroit, MI., Feb. 27, 1997, vol. 1229, Feb., 1997, pp. 83 88, XP002075840. *

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6742632B2 (en) * 1998-12-01 2004-06-01 Lucas Industries Plc Apparatus with vibration-damped component, especially a brake
US6412880B1 (en) * 2000-03-29 2002-07-02 Honeywell Commercial Vehicle Systems Co. Combined power supply and electronic control circuit for ABS
US6302244B1 (en) * 2000-04-07 2001-10-16 The Boeing Company Brake squeal attenuator apparatus and method
US20040174067A1 (en) * 2003-03-07 2004-09-09 Advics Co., Ltd. Vehicle brake squeal control device
US6957875B2 (en) * 2003-03-07 2005-10-25 Advics Co., Ltd. Vehicle brake squeal control device
US20040178675A1 (en) * 2003-03-13 2004-09-16 Advics Co., Ltd. Vehicle brake squeal control device
US6923513B2 (en) * 2003-03-13 2005-08-02 Advics Co., Ltd. Vehicle brake squeal control device
US7021727B2 (en) * 2003-04-15 2006-04-04 Advics Co., Ltd. Vehicle brake system for preventing brake noise
US20040206589A1 (en) * 2003-04-15 2004-10-21 Masahiko Kamiya Vehicle brake system for preventing brake noise
US20050039990A1 (en) * 2003-07-25 2005-02-24 Messier-Bugatti Actuator for an electromechanical brake, a brake including such an actuator, a vehicle including at least one such brake, and a method of implementing said actuator
US20090277730A1 (en) * 2003-07-25 2009-11-12 Messier-Bugatti Actuator for an electromechanical brake, a brake including such an actuator, a vehicle including at least one such brake, and a method of implementing said actuator
US7703580B2 (en) * 2003-07-25 2010-04-27 Messier-Bugatti Actuator for an electromechanical brake, a brake including such an actuator, a vehicle including at least one such brake, and a method of implementing said actuator
US20050242664A1 (en) * 2004-04-29 2005-11-03 Thrush Christopher M Brake force sensor
US7232013B2 (en) * 2004-04-29 2007-06-19 Delphi Technologies, Inc. Brake force sensor
US20060108861A1 (en) * 2004-11-23 2006-05-25 Mando Corporation Electronic control brake system with piezoelectric actuator

Also Published As

Publication number Publication date
JPH10311354A (ja) 1998-11-24
EP0878634A1 (en) 1998-11-18
KR19980086867A (ko) 1998-12-05

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